WO 2010/151580 A1 describes an air filter that includes a bellows-like filter medium body for filtering air that comprises a plurality of connecting filter segments and is wound in a meandering manner. The outer filter segments of the filter medium body are embodied elongated and delimit an admission opening for the air to be cleaned, wherein the inner filter segments of the filter medium body run in a plurality of connecting loops. The filtration surface area is enlarged by the wound embodiment of the filter medium body.